1. Field of the Invention
The invention lies in the sphere of internal combustion engine gas-operated fixing devices. They operate on the principle of explosion of an inflammable mixture of gas and air in the combustion chamber of the engine, formed partly of a cylinder, a cylinder sleeve and a cylinder head, to propel into the cylinder a piston for driving a fixing device.
2. Description of the Related Art
The engine is arranged in a casing.
The case is arranged in the two shells of a handle to which it is fixed both at the front and at the rear. To be more specific, at the rear, the cylinder head of the engine, the casing and the handle shells are fixed together with the same bolts.
When the inflammable mixture in the combustion chamber is under pressure, a force directed towards the rear is exerted on the cylinder head and therefore on the casing to which it is connected.
Inversely, when, under the explosion action, the piston is propelled towards the front, it stops against a damper which is connected to the cylinder. A force directed forwards is thus exerted on the cylinder and therefore on the casing to which it is connected.
In brief, the casing, generally made from plastic, is subjected to a high degree of pressure stresses, up to 60% of all these stresses.
The casing of the gas-operated fixing devices already acts as a flexible damper since it manages to stretch a little.
The applicant realized that the casing was deforming where it was easiest for it, i.e. at the front of the equipment.
Therefore, from a situation in which a gas-operated fixing device casing is integral with the handle of the device, both at the front and at the rear, the applicant conceived the idea of trying to solve the problem of separating the front of the casing from the handle so as to enable the casing to perform better its function as a damper.
So it is that the invention covered by this application is proposed.